The funny thing about trying to replace paper money with gold is that the value of gold is actually just as intangible as the value of the printed paper. Intrinsically gold is quite worthless. You cannot eat it. It is a poor building material because it's so soft. Some properties make it a good choice in special cases like in electronics. But these use cases are in no relation at all to the value we assign to gold. One can argue that gold is pretty much as abstract a currency as the pure numbers in use today.